Efforts to control the human aging process can be explained in several different ways, and these interpretations have important practical consequences. Our research on "anti-aging medicine" suggests that whether a given research project, clinical intervention, or commercial product is interpreted as a medical treatment, a form of prevention, or an elective "enhancement" directly influences its evaluation against a number of scales, including its level of scientific legitimacy and public oversight, its potential social costs and benefits, and its moral status as a biomedical enterprise. In order for the scientific community and public policy makers to oversee developments in this area responsibly, a clear calculus of these influences and their implications is needed. We propose to address this need by combining empirical investigations of the ways in which biomedical efforts to control human aging are explained and understood with careful ethical and legal analyses of the different ways they are justified and promoted to the public. Our empirical studies will examine the promoters and clinicians who help frame anti-aging medicine, the consumers and patients who use their products and services, and the scientists and participants involved with the clinical trials of caloric restriction being undertaken by NIA. Our ethical and legal analyses will extrapolate the implications of these alternative interpretations for the regulation of anti-aging interventions and other biomedical advances that raise similar interpretive issues. We will pay special attention to the effects of framing anti-aging interventions as prevention against late-life disease, since this interpretation is dominant amongst active biogerontologists, appears to have unique ethical and policy implications, and illustrates issues that "personalized genomic medicine" will have to face more broadly, given its emphasis on risk detection and prevention. Lay Descripton: We propose to study the ways in which scientists, research subjects, clinicians and consumers explain their interests in controlling the human aging process, in order to help assess the policy implications of interpreting anti-aging interventions as prevention against late-life disease. This is important because a preventive interpretation carries moral weight, but may mask other social values that are challenged by efforts to control human aging.